Applications of plant nutrients are regularly made with aim to improve plant's yield and quality. Great efforts are made to concentrate compositions in terms of nutrients without fully understanding nutrient interactions and uptake efficiency by plants. In most instances fertiliser compositions are diluted in water and sprayed on plant's foliage or applied to the soil with the hope that they will be available for uptake by the plants. The mechanisms of nutrient uptake by plants is still under research and very little is known as to how the plant regulates nutrient absorption throughout its lifecycle with temporal variation of nutrient interactions at the different growth and development stages.
Plant nutrition alone can only achieve what is potential by the plant (not considering other contributing parameters such as crop protection and abiotic stresses) and most crop nutrition formulations are not providing nutrients adequately as they are typically applied on a hit-and-miss basis without understanding or affecting the plant nutrient absorption mechanisms. Therefore, the potential of the plant to produce is not achieved or improved.
Cytokinins have been shown to have effects on many physiological and developmental processes, including leaf senescence, nutrient mobilization, apical dominance, the formation and activity of shoot apical meristems, floral development, the breaking of bud dormancy, and seed germination. Cytokinins also appear to mediate many aspects of light-regulated development, including chloroplast differentiation, the development of autotrophic metabolism, and leaf and cotyledon expansion.
Cytokinins work typically in the presence of auxins and the most common first cytokinins are known as zeatin (natural) and kinetin (synthetic) regulating cell activities within the plant. Some synthetic compounds can mimic or antagonize cytokinin action. Cytokinins are defined as compounds that have biological activities which include the ability to do the following, i. induce cell division in callus cells in the presence of an auxin, ii. promote bud or root formation from callus cultures when in the appropriate molar ratios to auxin, iii. delay senescence of leaves and iv. promote expansion of dicot cotyledons.
Nearly all compounds active as cytokinins are N6-substituted amino-purines, such as benzyladenine (BA).

All the naturally occurring cytokinins are aminopurine derivatives. There are also synthetic cytokinin compounds that have not been identified in plants, such as thidiazuron, which is used commercially as a defoliant and an herbicide. It is also known that some molecules act as cytokinin antagonists. These molecules are able to block the action of cytokinins, and their effects may be overcome by the addition of more cytokinin.
Cytokinins can stimulate or inhibit a variety of physiological, metabolic, biochemical, and developmental processes when they are applied to higher plants, and it is increasingly clear that endogenous cytokinins play an important role in the regulation of these events in the intact plant. Cytokinins are also responsible for delaying senescence in leaves and alter the source-sink relationship of nutrients.
Mg2+ is essential for plant growth and the amounts of Mg2+ vary in different parts of the plant. Excess Mg2+ may be stored in vascular cells and in times of starvation Mg2+ is redistributed typically from older to newer leaves. When Mg2+ is taken up into plants via the roots which carry a great number of negative charges (key to the uptake of cations by root cells), due to the Mg2+ binding relatively weakly to these charges, it can be displaced by other cations, impeding uptake and causing deficiency in the plant. Within individual plant cells the Mg2+ requirements are largely the same as for all cellular life; Mg2+ is used to stabilise membranes, is vital to the utilisation of ATP, is extensively involved in the nucleic acid biochemistry, and is a cofactor for many enzymes (including the ribosome). Also, Mg2+ is the coordinating ion in the chlorophyll molecule. It is the intracellular compartmentalisation of Mg2+ in plant cells that leads to additional complexity. Four compartments within the plant cell have reported interactions with Mg2+. Initially Mg2+ will enter the cell into the cytoplasm (by an as yet unidentified system), but free Mg2+ concentrations in this compartment are tightly regulated at relatively low levels and so any excess Mg2+ is either quickly exported or stored in the second intracellular compartment, the vacuole.
When a Mg2+ ion has been absorbed by a cell requiring it for metabolic processes, it is generally assumed that the ion stays in that cell for as long as the cell is active. In vascular cells this is not always the case; in times of plenty Mg2+ is stored in the vacuole, takes no part in the day-to-day metabolic processes of the cell, and is released at need. But for most cells it is death by senescence or injury that releases Mg2+ and many of the other ionic constituents, recycling them into healthy parts of the plant. Additionally, when Mg2+ in the environment is limiting, some species are able to mobilise Mg2+ from older tissues. These processes involve the release of Mg2+ from its bound and stored states and its transport back into the vascular tissue, where it can be distributed to the rest of the plant. In times of growth and development Mg2+ is also remobilised within the plant as source and sink relationships change. Mg2+ is the coordinating metal ion in the chlorophyll molecule and in plants where the ion is in high supply about 6% of the total Mg2+ is bound to chlorophyll. Thylakoid stacking is stabilised by Mg2+ and is important for the efficiency of photosynthesis.
It is an object of the present invention to provide an improved agrochemical composition.
It is an object of the present invention to provide agrochemical compositions that increase crop yield and/or crop quality characteristics.
It is an object of the present invention to improve plant physiology.
It is an object of the present invention to provide agrochemical compositions that increase chlorophyll levels in plants.
It is a further object of the invention to provide agrochemical compositions that increase the photosynthetic rate in plants.
It is a further object of the invention to provide agrochemical compositions that increase foliar absorption of plant nutrients such as magnesium and/or iron.
It is yet a further object of the invention to provide agrochemical compositions that balance the phytohormonal activity of plants which optimise crop physiological characteristics.